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1 | /** @file\r |
2 | ACPI Timer implements one instance of Timer Library.\r | |
3 | \r | |
4 | Copyright (c) 2014, Intel Corporation. All rights reserved.<BR>\r | |
5 | This program and the accompanying materials are\r | |
6 | licensed and made available under the terms and conditions of the BSD License\r | |
7 | which accompanies this distribution. The full text of the license may be found at\r | |
8 | http://opensource.org/licenses/bsd-license.php\r | |
9 | \r | |
10 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
11 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
12 | \r | |
13 | **/\r | |
14 | \r | |
15 | #include <PiPei.h>\r | |
16 | #include <Library/TimerLib.h>\r | |
17 | #include <Library/BaseLib.h>\r | |
18 | #include <Library/IoLib.h>\r | |
19 | #include <Library/HobLib.h>\r | |
20 | #include <Library/DebugLib.h>\r | |
21 | \r | |
22 | #include <Guid/AcpiBoardInfoGuid.h>\r | |
23 | #include <IndustryStandard/Acpi.h>\r | |
24 | \r | |
25 | #define ACPI_TIMER_COUNT_SIZE BIT24\r | |
26 | \r | |
27 | UINTN mPmTimerReg = 0;\r | |
28 | \r | |
29 | /**\r | |
30 | The constructor function enables ACPI IO space.\r | |
31 | \r | |
32 | If ACPI I/O space not enabled, this function will enable it.\r | |
33 | It will always return RETURN_SUCCESS.\r | |
34 | \r | |
35 | @retval EFI_SUCCESS The constructor always returns RETURN_SUCCESS.\r | |
36 | \r | |
37 | **/\r | |
38 | RETURN_STATUS\r | |
39 | EFIAPI\r | |
40 | AcpiTimerLibConstructor (\r | |
41 | VOID\r | |
42 | )\r | |
43 | {\r | |
44 | EFI_HOB_GUID_TYPE *GuidHob;\r | |
45 | ACPI_BOARD_INFO *pAcpiBoardInfo; \r | |
46 | \r | |
47 | //\r | |
48 | // Find the acpi board information guid hob\r | |
49 | //\r | |
50 | GuidHob = GetFirstGuidHob (&gUefiAcpiBoardInfoGuid);\r | |
51 | ASSERT (GuidHob != NULL);\r | |
52 | \r | |
53 | pAcpiBoardInfo = (ACPI_BOARD_INFO *)GET_GUID_HOB_DATA (GuidHob); \r | |
54 | \r | |
55 | mPmTimerReg = (UINTN)pAcpiBoardInfo->PmTimerRegBase;\r | |
56 | \r | |
57 | return EFI_SUCCESS;\r | |
58 | }\r | |
59 | \r | |
60 | /**\r | |
61 | Internal function to read the current tick counter of ACPI.\r | |
62 | \r | |
63 | Internal function to read the current tick counter of ACPI.\r | |
64 | \r | |
65 | @return The tick counter read.\r | |
66 | \r | |
67 | **/\r | |
68 | UINT32\r | |
69 | InternalAcpiGetTimerTick (\r | |
70 | VOID\r | |
71 | )\r | |
72 | {\r | |
73 | if (mPmTimerReg == 0)\r | |
74 | AcpiTimerLibConstructor ();\r | |
75 | \r | |
76 | return IoRead32 (mPmTimerReg);\r | |
77 | }\r | |
78 | \r | |
79 | /**\r | |
80 | Stalls the CPU for at least the given number of ticks.\r | |
81 | \r | |
82 | Stalls the CPU for at least the given number of ticks. It's invoked by\r | |
83 | MicroSecondDelay() and NanoSecondDelay().\r | |
84 | \r | |
85 | @param Delay A period of time to delay in ticks.\r | |
86 | \r | |
87 | **/\r | |
88 | VOID\r | |
89 | InternalAcpiDelay (\r | |
90 | IN UINT32 Delay\r | |
91 | )\r | |
92 | {\r | |
93 | UINT32 Ticks;\r | |
94 | UINT32 Times;\r | |
95 | \r | |
96 | Times = Delay >> 22;\r | |
97 | Delay &= BIT22 - 1;\r | |
98 | do {\r | |
99 | //\r | |
100 | // The target timer count is calculated here\r | |
101 | //\r | |
102 | Ticks = InternalAcpiGetTimerTick () + Delay;\r | |
103 | Delay = BIT22;\r | |
104 | //\r | |
105 | // Wait until time out\r | |
106 | // Delay >= 2^23 could not be handled by this function\r | |
107 | // Timer wrap-arounds are handled correctly by this function\r | |
108 | //\r | |
109 | while (((Ticks - InternalAcpiGetTimerTick ()) & BIT23) == 0) {\r | |
110 | CpuPause ();\r | |
111 | }\r | |
112 | } while (Times-- > 0);\r | |
113 | }\r | |
114 | \r | |
115 | /**\r | |
116 | Stalls the CPU for at least the given number of microseconds.\r | |
117 | \r | |
118 | Stalls the CPU for the number of microseconds specified by MicroSeconds.\r | |
119 | \r | |
120 | @param MicroSeconds The minimum number of microseconds to delay.\r | |
121 | \r | |
122 | @return MicroSeconds\r | |
123 | \r | |
124 | **/\r | |
125 | UINTN\r | |
126 | EFIAPI\r | |
127 | MicroSecondDelay (\r | |
128 | IN UINTN MicroSeconds\r | |
129 | )\r | |
130 | {\r | |
131 | InternalAcpiDelay (\r | |
132 | (UINT32)DivU64x32 (\r | |
133 | MultU64x32 (\r | |
134 | MicroSeconds,\r | |
135 | ACPI_TIMER_FREQUENCY\r | |
136 | ),\r | |
137 | 1000000u\r | |
138 | )\r | |
139 | );\r | |
140 | return MicroSeconds;\r | |
141 | }\r | |
142 | \r | |
143 | /**\r | |
144 | Stalls the CPU for at least the given number of nanoseconds.\r | |
145 | \r | |
146 | Stalls the CPU for the number of nanoseconds specified by NanoSeconds.\r | |
147 | \r | |
148 | @param NanoSeconds The minimum number of nanoseconds to delay.\r | |
149 | \r | |
150 | @return NanoSeconds\r | |
151 | \r | |
152 | **/\r | |
153 | UINTN\r | |
154 | EFIAPI\r | |
155 | NanoSecondDelay (\r | |
156 | IN UINTN NanoSeconds\r | |
157 | )\r | |
158 | {\r | |
159 | InternalAcpiDelay (\r | |
160 | (UINT32)DivU64x32 (\r | |
161 | MultU64x32 (\r | |
162 | NanoSeconds,\r | |
163 | ACPI_TIMER_FREQUENCY\r | |
164 | ),\r | |
165 | 1000000000u\r | |
166 | )\r | |
167 | );\r | |
168 | return NanoSeconds;\r | |
169 | }\r | |
170 | \r | |
171 | /**\r | |
172 | Retrieves the current value of a 64-bit free running performance counter.\r | |
173 | \r | |
174 | Retrieves the current value of a 64-bit free running performance counter. The\r | |
175 | counter can either count up by 1 or count down by 1. If the physical\r | |
176 | performance counter counts by a larger increment, then the counter values\r | |
177 | must be translated. The properties of the counter can be retrieved from\r | |
178 | GetPerformanceCounterProperties().\r | |
179 | \r | |
180 | @return The current value of the free running performance counter.\r | |
181 | \r | |
182 | **/\r | |
183 | UINT64\r | |
184 | EFIAPI\r | |
185 | GetPerformanceCounter (\r | |
186 | VOID\r | |
187 | )\r | |
188 | {\r | |
189 | return (UINT64)InternalAcpiGetTimerTick ();\r | |
190 | }\r | |
191 | \r | |
192 | /**\r | |
193 | Retrieves the 64-bit frequency in Hz and the range of performance counter\r | |
194 | values.\r | |
195 | \r | |
196 | If StartValue is not NULL, then the value that the performance counter starts\r | |
197 | with immediately after is it rolls over is returned in StartValue. If\r | |
198 | EndValue is not NULL, then the value that the performance counter end with\r | |
199 | immediately before it rolls over is returned in EndValue. The 64-bit\r | |
200 | frequency of the performance counter in Hz is always returned. If StartValue\r | |
201 | is less than EndValue, then the performance counter counts up. If StartValue\r | |
202 | is greater than EndValue, then the performance counter counts down. For\r | |
203 | example, a 64-bit free running counter that counts up would have a StartValue\r | |
204 | of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter\r | |
205 | that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.\r | |
206 | \r | |
207 | @param StartValue The value the performance counter starts with when it\r | |
208 | rolls over.\r | |
209 | @param EndValue The value that the performance counter ends with before\r | |
210 | it rolls over.\r | |
211 | \r | |
212 | @return The frequency in Hz.\r | |
213 | \r | |
214 | **/\r | |
215 | UINT64\r | |
216 | EFIAPI\r | |
217 | GetPerformanceCounterProperties (\r | |
218 | OUT UINT64 *StartValue, OPTIONAL\r | |
219 | OUT UINT64 *EndValue OPTIONAL\r | |
220 | )\r | |
221 | {\r | |
222 | if (StartValue != NULL) {\r | |
223 | *StartValue = 0;\r | |
224 | }\r | |
225 | \r | |
226 | if (EndValue != NULL) {\r | |
227 | *EndValue = ACPI_TIMER_COUNT_SIZE - 1;\r | |
228 | }\r | |
229 | \r | |
230 | return ACPI_TIMER_FREQUENCY;\r | |
231 | }\r | |
232 | \r | |
233 | /**\r | |
234 | Converts elapsed ticks of performance counter to time in nanoseconds.\r | |
235 | \r | |
236 | This function converts the elapsed ticks of running performance counter to\r | |
237 | time value in unit of nanoseconds.\r | |
238 | \r | |
239 | @param Ticks The number of elapsed ticks of running performance counter.\r | |
240 | \r | |
241 | @return The elapsed time in nanoseconds.\r | |
242 | \r | |
243 | **/\r | |
244 | UINT64\r | |
245 | EFIAPI\r | |
246 | GetTimeInNanoSecond (\r | |
247 | IN UINT64 Ticks\r | |
248 | )\r | |
249 | {\r | |
250 | UINT64 Frequency;\r | |
251 | UINT64 NanoSeconds;\r | |
252 | UINT64 Remainder;\r | |
253 | INTN Shift;\r | |
254 | \r | |
255 | Frequency = GetPerformanceCounterProperties (NULL, NULL);\r | |
256 | \r | |
257 | //\r | |
258 | // Ticks\r | |
259 | // Time = --------- x 1,000,000,000\r | |
260 | // Frequency\r | |
261 | //\r | |
262 | NanoSeconds = MultU64x32 (DivU64x64Remainder (Ticks, Frequency, &Remainder), 1000000000u);\r | |
263 | \r | |
264 | //\r | |
265 | // Ensure (Remainder * 1,000,000,000) will not overflow 64-bit.\r | |
266 | // Since 2^29 < 1,000,000,000 = 0x3B9ACA00 < 2^30, Remainder should < 2^(64-30) = 2^34,\r | |
267 | // i.e. highest bit set in Remainder should <= 33.\r | |
268 | //\r | |
269 | Shift = MAX (0, HighBitSet64 (Remainder) - 33);\r | |
270 | Remainder = RShiftU64 (Remainder, (UINTN) Shift);\r | |
271 | Frequency = RShiftU64 (Frequency, (UINTN) Shift);\r | |
272 | NanoSeconds += DivU64x64Remainder (MultU64x32 (Remainder, 1000000000u), Frequency, NULL);\r | |
273 | \r | |
274 | return NanoSeconds;\r | |
275 | }\r | |
276 | \r |